The invention relates to an apparatus and method for detecting improperly capped bottles, and in particular to a signal emission and detection device that detects substantially all low cap, high cap, or cocked cap bottles regardless of the bottle cap radial orientation relative to the detection device.
In the automated process of filling and capping bottles, it is of substantial importance to detect a miscapped bottle so that such a product can be removed from production. An improperly sealed bottle may not properly protect the bottle contents from microbial activity. An unsealed bottled product is generally not acceptable. Moreover, air sensitive bottled liquids, whether pasteurized or hot fill, may spoil without proper capping.
An undetected miscapped bottle may also result in fluid leakage from the bottle particularly during high-speed bottling production processes. Miscapped bottles may readily spill their contents onto production equipment resulting in heightened production costs due to additional clean-up efforts. Leakage from miscapped containers may damage production equipment thereby requiring unscheduled production downtime to isolate the damage and repair the equipment.
One current method utilized to detect miscapped bottles is photodetection. Photodetection typically entails placing a single photoemitter and photoreceiver on opposing sides of a conveyor transporting capped bottles. The photoemitter has a light source and directs a beam of light to the photoreceiver. The photoemitter and photoreceiver are interconnected to a controller such that various parameters of the bottle can then be monitored by the interruption or noninterruption of the light beam. For instance, a photodetector can be placed at a position such that the light beam impacts the cap when a bottle has a cap. A bottle passing through the detector without a cap would not interrupt the light beam. In this scenario, the controller would generate a xe2x80x9cno capxe2x80x9d signal. In a similar manner, photodetection systems are employed to detect a high cap, a low cap or a cocked cap.
Despite these varied applications, a high percentage of miscapped bottles escape detection by current photodetection systems. Oftentimes, the photodetector is unable to distinguish between a properly sealed cap and an improperly sealed cap. For instance, current photodetection systems cannot distinguish between a properly sealed cap and a bottle with a cocked cap when the cap gap is in line with the photodetector""s light beam. Both types of bottles can pass through the photodetection system as properly capped.
A need therefore exists for an apparatus and method that can detect substantially all miscapped bottles in a bottle line process. Subsequently, a need exists for an apparatus and method that can distinguish between properly capped bottles and miscapped bottles. More specifically, a need exists for an apparatus and method that can detect a miscapped bottle regardless of the cap""s radial orientation relative to the system designed to detect it.
The present invention provides an apparatus and method that detects an improperly capped bottle regardless of the cap""s radial orientation relative to the detecting apparatus. The apparatus comprises at least two signal emitters wherein each emits a signal beam to a signal detector. Each emitter is positioned to direct the signal beam to a different cap target location. Each emitter is further positioned at a predetermined height. This height is based upon the height of a properly positioned cap relative to the bottle. Generally, the apparatus positions the emitters so that the signal beams are in a plane normal or substantially normal to the vertical axis of the bottle. The signal beams are radially spaced from each other so that the detector is able to identify a proper cap, high cap, low cap, or a cocked cap by either the presence or absence of detection of the signal beam.
In accordance with another aspect of the invention, the emitters operate simultaneously when directing their respective signal beams to the detectors.
In accordance with another aspect of the invention the signal beam is a highly focused narrow beam of light. Any light source may be utilized by the present invention including, but not limited to, laser, x-ray, visible, ultra-violet, infrared or far red, for example.
In accordance with another embodiment of the present invention, the signal beams are directed across the plane defined by the top of a properly placed cap.
In accordance with another aspect of the invention, the angle of radial spacing between emitters is in the range of about 45 degrees and about 90 degrees.
In accordance with another embodiment of the present invention, the signal beams are directed at target points that are tangential to the plane defined by the bottom of a properly placed cap.
In accordance with another embodiment of the present invention, the bottle cap has a circumferential reflective or absorptive band located on the side of the bottle cap. The signals are emitted at target points that are located on this reflective band for a properly placed bottle cap. A properly positioned cap is detected by the presence or absence of a signal beam reflected off of the reflective or absorptive band.
In accordance with another aspect of the present invention, a method of detecting an improperly capped bottle is provided comprising the steps of:
Providing a detector system having two signal emitters and two corresponding signal detectors; positioning each signal emitter to direct a signal to a different cap target location; directing the signals at a predetermined height relative to the cap in a plane normal to the vertical cap axis; and indicating whether the presence or absence of a signal detected by the signal detector is one or more incorrect cap positions selected from the group consisting of high cap, low cap and cocked cap.